Measurement of the relative phase between the strong and electromagnetic amplitudes in J/ψ→ Σ⁺ Σ̅⁻

@misc{collaboration2026measurement,
  title = {{Measurement of the relative phase between the strong and electromagnetic amplitudes in $\boldsymbolJ/ψ\to Σ^+ \barΣ^-$}},
  author = {BESIII Collaboration and M. Ablikim and M. N. Achasov and P. Adlarson and X. C. Ai and C. S. Akondi and R. Aliberti and A. Amoroso and Q. An and Y. H. An and M. S. Anderson and Y. Bai and O. Bakina and H. R. Bao and X. L. Bao and M. Barbagiovanni and V. Batozskaya and K. Begzsuren and N. Berger and M. Berlowski and M. B. Bertani and D. Bettoni and F. Bianchi and E. Bianco and A. Bortone and I. Boyko and R. A. Briere and A. Brueggemann and D. Cabiati and H. Cai and M. H. Cai and X. Cai and A. Calcaterra and G. F. Cao and N. Cao and S. A. Cetin and X. Y. Chai and J. F. Chang and T. T. Chang and G. R. Che and Y. Z. Che and C. H. Chen and Chao Chen and G. Chen and H. S. Chen and H. Y. Chen and M. L. Chen and S. J. Chen and S. M. Chen and T. Chen and W. Chen and X. R. Chen and X. T. Chen and X. Y. Chen and Y. B. Chen and Y. Q. Chen and Z. K. Chen and J. Cheng and L. N. Cheng and S. K. Choi},
  howpublished = {arXiv},
  year = {2026},
  month = oct,
  doi = {10.48550/arxiv.2610.26673},
  eprint = {2610.26673},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2610.26673},
}

TY  - UNPB
TI  - Measurement of the relative phase between the strong and electromagnetic amplitudes in J/ψ→ Σ^+ Σ̅^−
AU  - BESIII Collaboration
AU  - M. Ablikim
AU  - M. N. Achasov
AU  - P. Adlarson
AU  - X. C. Ai
AU  - C. S. Akondi
AU  - R. Aliberti
AU  - A. Amoroso
AU  - Q. An
AU  - Y. H. An
AU  - M. S. Anderson
AU  - Y. Bai
AU  - O. Bakina
AU  - H. R. Bao
AU  - X. L. Bao
AU  - M. Barbagiovanni
AU  - V. Batozskaya
AU  - K. Begzsuren
AU  - N. Berger
AU  - M. Berlowski
AU  - M. B. Bertani
AU  - D. Bettoni
AU  - F. Bianchi
AU  - E. Bianco
AU  - A. Bortone
AU  - I. Boyko
AU  - R. A. Briere
AU  - A. Brueggemann
AU  - D. Cabiati
AU  - H. Cai
AU  - M. H. Cai
AU  - X. Cai
AU  - A. Calcaterra
AU  - G. F. Cao
AU  - N. Cao
AU  - S. A. Cetin
AU  - X. Y. Chai
AU  - J. F. Chang
AU  - T. T. Chang
AU  - G. R. Che
AU  - Y. Z. Che
AU  - C. H. Chen
AU  - Chao Chen
AU  - G. Chen
AU  - H. S. Chen
AU  - H. Y. Chen
AU  - M. L. Chen
AU  - S. J. Chen
AU  - S. M. Chen
AU  - T. Chen
AU  - W. Chen
AU  - X. R. Chen
AU  - X. T. Chen
AU  - X. Y. Chen
AU  - Y. B. Chen
AU  - Y. Q. Chen
AU  - Z. K. Chen
AU  - J. Cheng
AU  - L. N. Cheng
AU  - S. K. Choi
PY  - 2026
DA  - 2026/10/19
PB  - arXiv
DO  - 10.48550/arxiv.2610.26673
UR  - https://arxiv.org/abs/2610.26673
AB  - Using 284 pb^−1 of e^+e^− collision data collected with the BESIII detector at center-of-mass energies between 3.00 and 3.12 GeV, the relative phase between the strong and electromagnetic interaction amplitudes in the process J/ψ→ Σ^+ Σ̅^- is determined. The relative phase is measured to be (107.9 ± 24.9)^∘ or (−107.6 ± 24.3)^∘, where the uncertainty includes both statistical and systematic sources. This is the first experimental determination of the strong-electromagnetic phase difference in J/ψ decays to a hyperon-antihyperon pair. The branching fraction ℬ_J/ψ→ Σ^+ Σ̅^- is measured to be (1.14 ± 0.04)× 10^−3 for the positive phase solution or (1.19 ± 0.04) × 10^−3 for the negative phase solution. These results provide important input for testing perturbative QCD predictions and studies of SU(3) flavor symmetry.
ER  -